Hi Kumar,

There is no frontend API to get this but this is covered by the vSphere Web Services SDK (vim25). 

I believe what you need is the VirtualCenter.InstanceName setting that you can view in the following MOB location: https://VCENTER_IP/mob/?moid=VpxSettings&doPath=setting%5b%22VirtualCenter%2eInstanceName%22%5d

If this is not sufficient please ask in the vSphere Management SDK forum.

Cheers,

Vladi